Highly efficient light-induced self-assembly of gold nanoparticles promoted by photoexcitation-induced aggregatable ligands.

There are numerous ways to achieve light-induced self-assembly of gold nanoparticles, but most of them are through chemical reaction and slow. Ligands that can perform photoexcitation-induced aggregation were synthesized and modified onto gold nanoparticles. The leading functionalized nanoparticles exhibit highly efficient light-induced self-assembly properties and show high-contrast color fading in tens of seconds.

Water molecular bridge-induced selective dual polarization in crystals for stable multi-emitters.

In the solid state, the molecular polarization of donor-acceptor (D-A) molecules can be implemented in a simple way via the use of an external polarizing source (e.g., an electric field). However, internal chemical polarization approaches are less studied due to difficulties related to controlling the charge-separation orientation in the solid state. Herein, a series of D-A molecules with both a proton donor and an acceptor were designed. Water-based molecular bridges were then established in their crystal structures, which firmly and alternately connected the proton donor of one molecule and the acceptor of another via an intermolecular H-bond network. In this way, the selective dual polarization of a phenolic hydroxyl group and a pyridinyl group could be achieved, owing to the strengthening of the charge-separation orientation upon the simultaneous deprotonation and protonation of the D-A molecules. This effect led to a 3-5-fold amplification of the molecular dipole moment in the crystal form relative to the monomeric state. On this basis, multi-excitation and multi-emission characteristics were achieved in these charge-separated crystals, endowing them with the ability to visually detect the energy of a light source, covering a wide range of the UV-Vis spectral region. This work provides a practical chemical approach for developing intrinsically polarized systems that can exhibit stable but distinct molecular photophysical properties.

Base-free oxidation of alcohols enabled by nickel(ii)-catalyzed transfer dehydrogenation.

An efficient nickel(ii)-catalyzed transfer dehydrogenation oxidation of alcohols is reported that relies on cyclohexanone as the formal oxidant and does not require the use of an external base. The synthetic utility of this protocol is demonstrated via the facile oxidation of structurally complicated natural products.

Cesium Carbonate Catalyzed Esterification of N-Benzyl-N-Boc-amides under Ambient Conditions.

We report a general activated amide to ester transformation catalyzed by Cs2CO3. Using this approach, esterification proceeds under relatively mild conditions and without the need for a transition metal catalyst. This method exhibits broad substrate scope and represents a practical alternative to existing esterification strategies. The synthetic utility of this protocol is demonstrated via the facile synthesis of crown ether derivatives and the late-stage modification of a representative natural product and several sugars in reasonable yields.

Cryptotanshinone Regulates Androgen Synthesis through the ERK/c-Fos/CYP17 Pathway in Porcine Granulosa Cells.

The aim of the study is to investigate the molecular mechanism behind androgen reduction in porcine granulosa cells (pGCs) with Salvia miltiorrhiza Bunge extract cryptotanshinone. PGCs were isolated from porcine ovaries and identified. Androgen excess model of the pGCs was induced with the MAPK inhibitor PD98059 and then treated with cryptotanshinone. The testosterone level was measured by radioimmunoassay in the culture media. The protein levels of P-ERK1/2, c-Fos, and CYP17 in the cells were measured by western blot. Cryptotanshinone decreased the concentration of testosterone and the protein level of CYP17 and increased the protein levels of P-ERK1/2 and c-Fos in the androgen excess mode. After the c-Fos gene was silenced by infection with c-Fos shRNA lentivirus, we measured the mRNA expression by quantitative RT-PCR and protein level by western blot of P-ERK1/2, c-Fos, and CYP17. This showed that the mRNA expression and protein level of P-ERK1/2 and c-Fos were significantly reduced in the shRNA-c-Fos group compared to the scrambled group, while those of CYP17 were significantly increased. So we concluded that cryptotanshinone can significantly reduce the androgen excess induced by PD98059 in pGCs. The possible molecular mechanism for this activity is regulating the ERK/c-Fos/CYP17 pathway.

[Effective Ingredients of Yangjing Zhongyu Decoction Regulated Androgen Biosyntheses by Mitogen-Activated Protein Kinase Pathway in Porcine Granulose Cells].

OBJECTIVE: To study the molecular mechanism of Yangjing Zhongyu Decoction (YZD) n-butanol extracts (ZDC) and ethyl acetate extracts (YSYZ) in reducing androgen in porcine granulose cells by mitogen-activated protein kinase (MAPK) pathway. METHODS: Porcine granulose cells were isolated and cultured. They were inoculated by MAPK inhibitor PD98059 at different concentrations, and then they were divided into the blank control group (0), 1, 3, 10, and 25 micromol/L groups. After 24-h culture the cytochrome P450c17a (CYP17) mRNA expression level was detected using Real-time fluorescent quantitative PCR. Contents of androgen (testosterone) in the supernate were detected using RIA and optimal PD98059 concentration screened. After intervened by 10 micromol/L PD98059 for 24 h, the culture solution was intervened by effective ingredients of with or without YZD or YSYZ at various concentrations (0, 1 , 5, 25, 50 mg/mL) at various time points (3, 6, 18, 24 h). Expression levels of p-ERK1/2, c-Fos and CYP17 were detected by Western blot. Testosterone content in the supernate was determined by radioimmunoassay (RIA). RESULTS: Ten pLmol/L PD98059 could obviously decrease p-ERK1/2 protein expression and increase CYP17 mRMA expression, and elevate testosterone content in the supernate (P < 0.05). ZDC and YSYZ at 25 ng/mL could increase p-ERK1/2 protein expression and c-Fos levels, and reduce CYP17 protein expression, and lower testosterone content in the supernate after 6-h intervention (P < 0.01). CONCLUSION: Effective ingredients of YZD could reduce androgen production in porcine granulose cells through increasing activities of MAPK.

[Effect of low-frequency electroacupuncture intervention on oxidative stress and glucose metabolism in rats with polycystic ovary syndrome].

OBJECTIVE: To observe the effect of low-frequency electroacupuncture (EA) treatment on oxidative stress and metabolism disorder in polycystic ovary syndrome (PCOS) rats, so as to study its underlying mechanisms in improving PCOS. METHODS: Thirty female SD rats were randomized into control group, model group and EA group (n = 10 in each group). The PCOS model was established by subcutaneous injection of testosterone propionate (1 mg/100 g, 10 mg/mL) for 8 weeks. EA (2 Hz) was applied to "Zhongwan" (CV 12) , "Guanyuan" (CV 4) and bilateral "Sanyinjiao" (SP 6) or "Housanli" (ST 36) for 30 min, once daily (except weekends) for 5 weeks. Serum testosterone (T) , sex hormone-binding globulin (SHBG) and fasting serum insulin (FINS) contents were detected by ELISA, serum malondialdehyde (MDA) and superoxide dismutase (SOD) levels were assayed by thiobarbituric acid (TBA) and xanthine oxidation (XTO) methods, respectively, and fasting blood glucose (FBG) was determined by roche glucose meter. In addition, homeostasis model assessment for insulin resistance (HOMA-IR) and modified B cell function index (MBCI) were calculated. RESULTS: Compared with the control group, serum T, FBG, FINS, HOMA-IR, and serum MDA levels were significantly increased in the model group (P < 0.01), while serum SHBG, MBCI and SOD levels were considerably decreased in the model group (P < 0.01). Following EA treatment, all the increased serum T, FBG, FINS, HOMA-IR, and serum MDA levels, and the decreased serum SHBG, MBCI and SOD levels were reversed obviously (P < 0.05, P < 0.01). CONCLUSION: EA treatment may normalize insulin sensitivity, ameliorate insulin resistance and hyperinsulinemia in PCOS rats, probably by regulating the function of pancreatic islets ß cell and by reducing oxidative stress and free androgen.

[Effect of Yangjing Zhongyu Decoction on mRNA and protein expression of PCNA, StAR, and FSHR in ovarian granulosa cells cultured by excess androgen].

OBJECTIVE: To observe the effect of Yangjing Zhongyu Decoction (YZD) on mRNA and protein expression of PCNA, StAR, and FSHR in ovarian granulose cells (GCs) cultured by excess androgen. METHODS: Ovarian GCs from porcine follicles were isolated and cultured in vitro. Follicular stimulating hormone (FSH) or YZD was added in the GCs treated by excess testosterone propionate. Totally 48 h later mRNA and protein expression of PCNA, StAR, and FSHR were detected by RT-PCR and Western blot. RESULTS: Excess androgen inhibited mRNA and protein expression of PCNA, StAR, and FSHR of GCs. FSH and YZD could antagonize inhibition of excess androgens, and promote mRNA and protein expression of PCNA, StAR, and FSHR in GCs. CONCLUSION: YZD could antagonize the inhibition of excess androgen on mRNA and protein expression of PCNA, StAR and FSHR in GCs. Thus, we inferred that YZD could improve the follicle dysplasia by promoting mRNA and protein expression of PCNA, StAR and FSHR in GCs.